1. Technical Field
The present invention relates to an efficient bending device for a long tube made of metal such as a steel tube, a stainless steel tube, a copper tube, a titanium tube and an aluminum tube.
2. Background Art
A double bender having two right and left units of pressure die unit disclosed in JP-B-8-29358, for example, has been conventionally proposed as the above-mentioned type of bending device (bender device). In the right and left double bending type of bender, a bending unit mechanism has a single structure and is arranged to freely move up and down with respect to a horizontal position of a long tube, which is held, and a chuck mechanism portion is interlocked with a feeding mechanism operating in a back and forth direction on a moving pedestal while the moving pedestal is arranged to be capable of parallel movement in the right and left direction.
Further, as another known tube bending device, there has been proposed a tube bending device in which bending is carried out for a plurality of locations to be processed, which are provided in a direction of an axis core of a tube, in a respectively predetermined bending direction in accordance with respective setting. Such kind of device comprises a tube twisting unit for chucking an end of a tube to be processed, rotating the tube about a core of its axis to set a predetermined processing direction and moving the tube in a direction of the axis core to set the tube at a predetermined processing location and a tube bending unit for clamping and rotating at a predetermined angle the tube to be processed to perform bending, the tube bending unit being capable of moving in a longitudinal direction of the tube to be processed. Such a device is generally called a CNC bender (see JP-B-8-29358, JP-A-9-308918, JP-A-9-29346, JP-A-7-232219 and JP-B-8-9063).